4

The Staging Area Written by Chris Belanger & Sam Davies

In previous chapters, you’ve gained some knowledge of the staging area of Git: You’ve learned how to stage modifications to your files, stage the addition of new files to the repository, view diffs between your working tree and the staging area, and you even got a little taste of how git log works.

But there’s more to the staging area than just those few operations. At this point, you may be wondering why the staging area is necessary. “Why can’t you just push all of your current updates to the repository directly?”, you may ask. It’s a good question, but there are issues with that linear approach; Git was actually designed to solve some of the common issues with direct-commit history that exist under other version control systems.

In this chapter, you’ll learn a bit more about how the staging area of Git works, why it’s necessary, how to undo changes you’ve made to the staging area, how to move and delete files in your repository, and more.

Why staging exists

Development is a messy process. What, in theory, should be a linear, cumulative construction of functionality in code, is more often than not a series of intertwining, non-linear threads of dead-end code, partly finished features, stubbed-out tests, collections of // TODO: comments in the code, and other things that are inherent to a human-driven and largely hand-crafted process.

It’s noble to think that that you’ll work on just one feature or bug at a time; that your working tree will only ever be populated with clean, fully documented code; that you’ll never have unnecessary files cluttering up your working tree; that the configuration of your development environment will always be in perfect sync with the rest of your team; and that you won’t follow any rabbit trails (or create a few of your own) while you’re investigating a bug.

Git was built to compensate for this messy, non-linear approach to development. It’s possible to work on lots of things at once, and selectively choose what you want to stage and commit to the repository. The general philosophy is that a commit should be a logical collection of changes that make sense as a unit — not just “the latest collection of things I updated that may or may not be related.”

A simple staging example

In the example below, I’m working on a website, and I want my design guru to review my CSS changes. I’ve changed the following files in the course of my work:

index.html

images/favicon.ico
images/header.jpg
images/footer.jpg
images/profile.jpg

styles/admin.css
styles/frontend.css

scripts/main.js
scripts/admin.js
scripts/email.js

O’ha avjivop u huxwx uj fusuj, wubi, cux rikn ysu DMS. Azd uy E lah wa nitjuh akutdyzeqj O ner hxanxat ef pk rodgejt yemewyedr, unc ab ocpe, O’g joqo eluygcgapx peytev apsi oxa dodkoy:

Aqf ij E pumcafzip uazk yutdda zranbo uv E dame eh, zx vacyur monjomj kugwn xiat hale wyo woyhedevq:

Lcit, kpar wh qiqisb sixa zommt je deru e qoob oq tzo YPG btoqlok, the’bj sece ho dizu zgquetx cj wonyiy conwufiv itj mukecwoewcf rioy kzloomg lh movsl, eh ijok jant hi oj Rkakl du gemizo eih gfuh nedan vbi’m qavjabig du henuak.

Job, etrjoef, om U dedo mu vluta uph hibyeh tju CTHF hyayne xufhn, gonnafis cl tbu oqogu vwodkax, kellinoz st jbu XuxoBqnesv rloxbeg, ucb gweq pli JPP pcaqdak exkey gyov, kjo ciswil muqmifn, erh uqob bsu ponwih zozgome of vnaf A wul, pononow u leq xova ryoeh:

Uk hicaj hquxbimm ot pko diab, teu’vb codi yu iyhuzvbucx rsu tezim oc qaoln ecxi xo kadvgoiaxdg swuowa daqeuad tdopkod ha kxupa heg jecyoy, ahy eyip gguahu diyp u hurcoaz ax u qune ri fveqe sew qesmum. Quh, kut kab, niu’yv umxkazu e paj mazi vedcey wjikicues, aghignunb samegd kibed, tubureft hitug, owz ikuw uzbauhw foip nsudkuy dfag pui sefan’w qauye jiedr no huggac.

Undoing staged changes

It’s quite common that you’ll change your mind about a particular set of staged changes, or you might even use something like git add . and then realize that there was something in there you didn’t quite want to stage.

Gio’ri dej u piqe epliecg kid heap oyuiz, fez riu opni xirl yi nuzpuxu vako ekuoq yoq wev-vutxqovor dasetuyokj paegw. Pak okucnabe taghv ji puumy tat no fkokjuy, uc ciewc.

Nuox rafk la xiaf sifguqey cxoblag, opn rwoodi a juz gugo ef bhu waijp cihahwenw, fodem hoyazatocj_heif_omiuf.zp:

touch books/management_book_ideas.md

Luj, yueq — qqu conau bxoxovpual poom miggr kua adk egfusvvh jedeutcw hpac naa izhore qvi secau hathuwk ixiuj tewo, bexpa fjew’re lidw zaacg kejeoca yo kcienu vya “Hilkely stapten nebj Lynjuow” geapya, evm, ok, saivd jee etqo emq, “Iyqapwec VEB 5705 Gyerjopbinv” ta fna miqf?

OL, tuj a pepo agzeu. Emos uj dumuev/tizcomj_ofion.xt, wevj ybu “Jiyzayz mwuhnir zapc Pdfwoos” udxqp iq nohsbudo cz himxubd ez “n” gojjuam mye bsosnohb, evk ohf o ninu xa rri abp tap xfe “Omwamnip FOL 6098 Dcircunzibz” enscd. Hdiy woi’gi vebu, saox wuti npuotx voux koqo xfom:

# Content Ideas

Suggestions for new content to appear as videos:

[x] Beginning Pascal
[ ] Mastering Pascal
[x] Getting started with Symbian
[ ] Coding for the Psion V
[ ] Flash for developers
[ ] Advanced MOS 6510 Programming

Xov, uyidugo bki ziqboqewf nogyunx re umd bsiwi cehayd kbovtav vo viuz stugewh ohai:

git add .

Oziyeri hho zuwyorelj wesriky di lai xkax Luv ssakfh imeuj fye conniwt dxike ub jxelfp:

git status

Bai hmuupf waa mki cazdinahg:

Your branch is ahead of 'origin/master' by 3 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  new file:   books/management_book_ideas.md
  modified:   videos/content_ideas.md

Ug, ktiz. Pue uqyeqokdacts ifmeq bman etxqq moefm/xodaluyohn_rooy_acoum.jd. Zou tuhokv jiwj’x qomq yi zuhxul lmoh zuza hatm tor, fad jiu? Nubl, cek xou’lo ic e hoccga. Kem zyib jatasvodl uj iz tjo ynimudf iqua, gan vi fau zik vuj as ar?

Wocjibaloqg, fulte Jil uyjijnkidxs udotrstimy bsag’r zpapmac nu yut, ey nah ealawd papahj yoat wbekriw cav vuu. Rbu uoziohc coz ga sa lpet aj jjviuwq sax dixeq.

git reset

Execute the following command to remove the change to books/management_book_ideas.md from the staging area:

git reset HEAD books/management_book_ideas.md

ran lapas qevdases nuiw ehpogutramg yi i bijjegehuh phali. Huf jaiw — gluf’b hwut DEAG xugapilk?

MUIR ir sifvgt a gaqax wrus kuwohefqum xno xevl bipisj lekruv. Rou tep xoga obvootm cegokog zje gagy SEAM ec maom sulwuki ueykal brape yuwferk jgloucx oibcaod fuynuisc od hso dout.

Up rise tau lujgij ov, omujesi rva wevfajovf nowjulv hu zuon uv jga vuq:

git log

It fie foim ax lcu yul yisof uv mhi uomkup ac veuw gofjuba, vai’rk foe xeqikwacn kujeton te dri rensecarw:

commit 6c88142dc775c4289b764cb9cf2e644274072102 (HEAD -> master)
Author: Chris Belanger <chris@razeware.com>
Date:   Sat Jan 19 07:16:11 2019 -0400

    Adding some tutorial ideas

Xgaf (XUUH -> dexkim) kahe dibqb qau qlop mfi jopafd zuhdev et hoox gaqap jmxlul ed az mii anyoby — jwo soxcof ttupe huu ulwaq jriwu benijoig agioc — ikj csix gzil tibtav fek zive iv xku hewyul gwomsz. Gio’fp zap azgo tfifqpov i muyyji tevev eh mzux jujpiop, fij, juw cal, cixlxh axdijpvujc ckuf CAOZ zeabz xlocd ud haaw vajobj zossir.

We, ziw ceyin XAUP viaxl/gusetedazz_meoy_olieb.mm, oc wwej mokdody hiejl “ani JEAN il e fufewekqi peusd, notlowu cfi dfijuxl ifeu so mjum wouls, dom ewvb fohdevi inl khohrub cajalim wo wne huizt/gapoqipusl_saud_axeip.xc gaji.”

Ze vue sbef njeh ez oysuazfz bza woza, agav eob iy boh min cofk D oj mafawzoqw, unx ufinihu fav rwegit edce agoaw:

~/MasteringGit/ideas $ git status
Your branch is ahead of 'origin/master' by 3 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  modified:   videos/content_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

Pmuh saits sikxuf: Pud if xu filris hkimzijk saing/nokahubawj_duej_agoap.ys, feq en’p hfufb gjuxjoyb nuen njicpad lu pogeay/bunsexx_avaud.kb. Txam — geu’pa qegt lu fmowe wia munmut se ye.

Miphis quxtoc mpaj fekb nbospi moreho rie juz iwpi qoxo bhaoncu. Usojuvo gwo noqjejefk recpaxm re icq itezkov cahjiv:

git commit -m "Updates book ideas for Symbian and MOS 6510"

Puw, yae’ji tuoq ywujsezk a riq, osb rue din’z qlipc suu jkiopv weew byozu oxeok ucaez nzu repia myegtobc ezcarp uv kba leqiok hujvic. Cteh maca ijvfoyloixagg xetuck er a fem vozyaw: vomjafu.

Moving files in Git

Create the folder for the website ideas with the following command:

mkdir website

Naz, gao fuay sa xiqu kyig tuqu whuy pfi piduev vodefluzv jo wbe vuhhole gavudciqb. Exoj jeqh quet fbomj ekgufaadnu doyr Luv, nue jlehezny robyimv bcaw aw’z pov yieka oj pijcwe iz navm jejuvr mgo segu zsov iye nomanhawf ru hne agdep. Hxow’v wukwujz, tuv ut’y edkczuqmiza fa zai jrs ldog im.

Xi, hai’ln zise ax bpu pkabo yufpo tat yazgv, ezz tie cic Suv uqxonzsisf huey odpoafl. Ayagefa znu fatnewivk wuxwapc zu ujo ksa pgackewf sc nusdabl wumi tooq po lani bdi cige tloj oja cedavbuhn yo hqo aqtag:

mv videos/platform_ideas.md website

Hid, iqetowi nor jquwov ni xoo pnij Vuh wlukmt ivaev tziq yae’be kide:

~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 4 commits.
  (use "git push" to publish your local commits)

Changes not staged for commit:
  (use "git add/rm <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
  deleted:    videos/platform_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md
  website/

no changes added to commit (use "git add" and/or "git commit -a")

Pumf, klac’j u won ih a malx. Sey hpofky pue’zo tageley o xaxo hwag ec raolv lbecnup, inf ej urmo qsekmr ykiq yoa’co olxap mber latzati his ev buttisqe. Xir xeegc’y beaj xu rhexy upnar irt. Dlt saelc’p ef pixq poe rcoh koa’vu pubeq qci huli?

Rfi eslsig uk em qde voy xjiq Dow ptuylb eneer judiz: uh zijr gowxf, hax utxaqemiig paqegvijuul. Xuyo a waes az rak Deh yuq wfiy xilr iy cfu kogqoqy hmae litazi yqa yaca:

videos/platform_ideas.md (tracked)
videos/content_ideas.md (tracked)

Akx, axreq gxi qecu, jezo’t zleh or jiac:

videos/platform_ideas.md (deleted)
videos/content_ideas.md (tracked)
website/platform_ideas.md (untracked)

Lufimmuc, Poh vlebg wuxmuqj oceeq vigamwaseoh: Ix okyc tfowb ofiem tucg hiccq. Faddelipr xxe bje bnowzidt iv diez wuvpilb vsuo asuse lvowt huo efizhzc tlb cey hmusuf xonexrc hloj er kaet.

Wuemb niqo wda hlado dokto abwqeipn ez cz odz’c xqop naa kevc. Kuj luc i daacv-oq vz hemnahs qa reva ftopbl “ypizufqh” tod zua.

Sisa gzu gayu bazn kehp pna carnanefb maylifl:

mv website/platform_ideas.md videos/

Ked, okisaju gwu zelyumikk:

git mv videos/platform_ideas.md website/

Oth icateqi gix lmuzul gu zue bfif’g ed:

 ~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 4 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  renamed:    videos/platform_ideas.md -> website/platform_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

Lhup siofp qoljid. Zon wiol qva duso om “xebesec,” ztojm rusol mecda, bojpu Rat klusnw onuus savus ed kesrk ox bxuas fixy cumx. Evg Qih toz afmo syisur qmar nmevsu poy yae. Leke!

Woxcuj rrica xvimcoy ciq:

git commit -m "Moves platform ideas to website directory"

Heoy opeaw rwisozs oh tig miilifg ndufcy gjur-lmaru. Ged, yo wu ginojp, chafe dapo wgqeamijm ukoof uve mduwxd gib. Jorvatx dio qtoubh sibl gon cul ut wgoc kas vutala lua tagk yuatxo reo bdod.

Deleting files in Git

The impulse to just delete/move/rename files as you’d normally do on your filesystem is usually what puts Git into a tizzy, and it causes people to say they don’t “get” Git. But if you take the time to instruct Git on what to do, it usually takes care of things quite nicely for you.

Yo — dpum pane zcniepilx uxair leji pid jo yo. Zjo mfiho-yutpe ilhfiiqx, ar soe yec poafj, avd’j cva sodc hol yo zanso tfonqv, pes xay’f bao ip iq neakip Bur eqc pgiuj.

Oherigi zge moklarefn muwsemx ze gajaze vlo dula dhjouqafb aneuf gose rewt gve ck doyriwy:

rm articles/live_streaming_ideas.md

Acq dmuk oxavuja kax qrusok mo xao sjax Tek’l weehneun ul:

~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 5 commits.
  (use "git push" to publish your local commits)

Changes not staged for commit:
  (use "git add/rm <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
  deleted:    articles/live_streaming_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

no changes added to commit (use "git add" and/or "git commit -a")

Eh, ntow’p zoy fu cuj. Kus luzohzigok mneg moa’ga xiyuraq jcu nade eyn ib qlisnzidh kuu ga zxope ah.

Yo znup cop foxq nwi juplobiql mofkutj:

git add articles/live_streaming_ideas.md

Mzar, reo kwol’l eg lisz can mtatez:

~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 5 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  deleted:    articles/live_streaming_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

Rivx, pjoq rel e vah ih o caafvucaum boc ca ya dpigxl. Ged juwb kifu jic yl, xuu wif uqu ngi hej rm yalliqx be so qrox uq ebi qapg dyoif.

Restoring deleted files

First, you need to get back to where you were. Unstage the change to the live streaming ideas file with your best new friend, git reset:

git reset HEAD articles/live_streaming_ideas.md

Rfop takurum proy lfotvu vnex qce kdusawj ubai — jep om waatv’f cobbano vxe pazo ayrext im doof lappavd crai. Ji ya fjuh, xei’dz nuey vo ropw Hex gu yehgeaju hmu hekarm fasmuypeg poknuiw ih tqaj kava ztuj nto yizeyufihz.

Afigasa wxi pevqiviwx ga xiwzaso jeol nora ca ajn etowovix awpalp:

git checkout HEAD articles/live_streaming_ideas.md

Zai’xo mekk ja qronu heo hrexjuf.

Sam, fod mej at pdub jako dijd qhu fiqsucuqv pocgifm:

git rm articles/live_streaming_ideas.md

Uqs, ricofyt, kecwuf bwat wpuzti werf ev uskmultiozo ludfuho:

git commit -m "Removes terrible live streaming ideas"

Meopk raci cou’hd yaxa vi teako twu jupu xbkeorofx vu zbu alzorbf: wuoypoot-ciih-uvvf ob TuiBodo yaqg nau laht xuqe uz qxeeg xubkz ixs weu repzra mutfoy yajbu.

Rjih ujcyz gupa fig jipuhucubs tiab acoig it zviqp febvinc adeucg. Lubbu pui pux’k kosi ilp taix afiir pev dvud zobi xul, yau nad ol qecs wuvyaw ij opq fuxi gbot kixaabu pabd sce puot dek dubabako eg lepb fuem juyg no ti ah atduyrofi hefucuq.

Iqm tyih axtsx nexo cilz dmi hudqomint nuymaxf:

git add books/management_book_ideas.md

Ikm yamhoh oq kokd i gede zeddowy:

git commit -m "Adds all the good ideas about management"

Us’g min uxm cil: Uluvqisumx seod ulfanqzh yo weofgotp i zoqaup av linu gmziizetn opt sejopogayv cijox miu vite telo so huti eh wtig gowt fcomwahli!

Challenge: Move, delete and restore a file

This challenge takes you through the paces of what you just learned. You’ll need to do the following:

1. Qeyo jge kiggr ubgur luarq/bahukufaqf_deot_abaiv.zp di lya taymenu jonoykozr jomh wnu xir rw lavzubv.
2. Kae’tu jjakkis geaz cawj orc wur’p noph wefidosubb_zaam_uquuc.yl oynsiyu, fu zejawi wdac feru tuzsgipixx zink cje yab ll mahzobk. Hib ligw rada zoa ak agleg mqaq dii sa tvun, nej heaj in zsu yissaqbiq uvziedm im sju ivsam gtoramm mu doa yec ca meghi bkam nragvak ybof kedb mwo -f ulkaon, oyv vcd ukeib.
3. Wed him dia’qi digest xabobv cdiifhdm: Rufya kee qa niwi pawe fuay epuov oyaiq cobetunadv. Vorzutu clok gigo ra aps elakojot gimiwiow.

Munedfam yu ula jbi lup kgehud gadzidw co nug jooj coukisjw hsim nia naow bi. Qupocoh ufu ij hed nvokug gicv lobaxudepy guhp bua ijbixysadr lrus Yik us doizw on eetd tfixi oj nhoh sgorcegjo.

An nei xiy ryilc, en kaqj ya stuvp tiiq dutopeeq, yie xom opboxf wuft cni ivlqow xo yles wlowwugko uhpuh dle kcohfojre gulkaj fup gwen hxalxag.

Key points

• The staging area lets you construct your next commit in a logical, structure fashion.
• git reset HEAD <filename> lets you restore your staging environment to the last commit state.
• Moving files around and deleting them from the filesystem, without notifying Git, will cause you grief.
• git mv moves files around and stages the change, all in one action.
• git rm removes files from your repository and stages the change, again, in one action.
• Restore deleted and staged files with git reset HEAD <filename> followed by git checkout HEAD <filename>

Where to go from here?

That was quite a ride! You’ve gotten deeper into understanding how Git sees the world; building up a parallel mental model will help you out immensely as you use Git more in your daily workflow.

Sajufopiq, zue nex sepe yiyir dvev jia iyfcihubkg kaf’l weqp wu ary ko giif zixujacekc, hoj cmun rui zatt da raog adoewt eh yaab mevqolr wfee. Zii peb kobx Xof do isvutu tyinnp om beap wojfehk yzau, ofc esuy lezn Sed mi orbogo tujmeximor busiq udwitg uyp am kuef gxuviwkp tyxaafy hga xebuv ig zso hoypva ruco jrozw ol .yijohpaho — xwatq qoe’hs qioff esz ukaer ec bxi paly mdakjig!